Professional installation will help reduce the potential for condensation. Exterior doors and skylights should be installed as close as possible to the interior finish. The space between the frame and the rough opening around the perimeter should be completely insulated. And the joint between the frame and the wall surface on both the interior and exterior sides of the patio door should be sealed.
Placement of Interior Curtains, Blinds, Shades and Valances
Interior accessories must not inhibit or impede the free circulation of air at the surface of the glazing. Any restriction of movement will result in “still” air, which will cool. This cooler air will lower condensation resistance and increase the likelihood of “sweating”.
Most houses are designed and built with the heat ventilation sources at the outer perimeter and often near exterior doors, windows and patio doors. This ensures that the air temperature will be higher in the vicinity with the desired effect of increasing condensation resistance. Care should be taken not to block the unrestricted movement of the warm air with furniture or other accessories. Doing so could increase the potential for condensation.
Stack Effect and Wind Exposure
Condensation is often worse on the second floor because of stack effect and wind exposure. Stack effect refers to the fact that warm air rises and therefore the warmer more moist air will be on the second story. Wind exposure means that the upper floor is more exposed to higher wind speeds, causing lower surface temperatures on glazed units. These two factors lead to more condensation on the upper level in a house.